Covering plate of insulating material for transformers and other hightension apparatus



Nov. 27,'1923. l 1,475,177

FISCHER K. GOVERTNG PLATE 0F INSULATTNG MATERIAL FOR TRANSFORMERS'AND OTHER HIGH TENSION APPARATUS Filed Dec. 10, 1914 Patented Nov. 27, 1923 `UNITI-:D STATES 15..1jar1r o KURT FISCHER, OF COLOGNE-BRAUNSFELD, GERMANY, ASSIGNOR T GENERAL ELEC- TRIC COMPANY, A CORPORATION OF NEW YORK.

. covnmNG PLATE or INSULATING MAzrEmALlron mRANsroRMERs AND OTHER HIGH- TENSION APPARATUS.

Application led December ing Material for Transformers and Other` High-Tension Apparatus, of which the 'following is a speciication, reference being had l0 therein to the accompanyingr drawing.

This invention relates,l to improvements in covers of insulating material for casings p transformers and other high-tension apparatus.

A transformer or other high ltension apparatus is often immersed in insulating oil Within a casin having a cover through which pass the high tension conductors from the apparatus. When 'a metal cover is used,

it must be spaced a considerable distance above the top o f the high tension apparatus to provide proper insulation and the high tension conductors from the apparatus must be heavily insulated where they ass through the cover. Such casings have lbeen heretofore provided with covers made of insulating material instead of metal, thus permitting a smaller spacing between the cover and the apparatus and the elimination or reduction of the insulation on the high tension conductors passing through the cover. This arrangement, however, results in concentrations of the electrostatic field where the high tension conductors pass through the 'cover and also along the upper edge of the metal wall of the casing where it meets the cover.

A primary object of rthis invention is to obviate this diiiculty, and according to the invention I provide an insulating cover inv combination of parts described hereinafter4 10', 1914. serial No.- 876,583.-

ied upon a container c. These layers cornprise two metallic rings` one of which, a,

is arranged adjacentv the leading-out duct h, whilst the other, 79, is arranged in spaced relation with .the ring a and adjacent the outer edge of the cover f andl electrically Price.

connected with the container c as at and y" in Fig. 2. The two layers are of a sultable size and spaced a suitable distance-apartso that the voltage strain is. distributed over the cover f and may be dealt with without fear of rupture.

The cover may be made by placing sheets of insulation one on another, inserting metallic layersin correct position between said insulating materia-l and then compressing the same. Another process ofmakin the device' consists in first winding the insulating material on a round or oval core and then pressing it. In this case the metallic layers will be wound with the insulating material.

A special advantage of this kindof leading-out duct is that the available spaceis utilized considerably better than when cylindrical leading-out ducts projecting to either side ofthe cover are provided. Leadingout ducts which project a considerable diserally been lled into houses heretofore byv leading the high-voltage conductors to an in- 'sulator mounted on av support. The conlvide a plate-shaped.,leadingfout device for closing; the wall duc-t,

. The plate-shaped device according' to my invention is principally composed` of insula- 'tion and is made in the 'form o a plate condenser. It may be used either alone or in combination with a' cylindrical insulator y for leading in the high-tension conductors.

Referring to Figs. 3 anda, such 'a pla-tem includes insulation in which is embedded the are correspondingly distributed.

metallic layers 'a and o, 0; The plate is mounted at 29, p and the leadingn duct is in the middle at f. The distance apart o--the metallic layers is so selected that the voltage,

caribe dealt with Without danger of rupture. Instead of the one duct f two or more may be' provided Wlien the metallic The entry of birds 'and insects into the transformer house is preilented by the plates, because they cover the Wall lduct like a wirr dow pane. When suitably constructed such a plate is able to directly take up the pull of the conductor, so that the heretofore vusual insulator located in front of the duct is i the plate constituting a plate condenser.

saved.

The cover plate'whether for a transformer' casmg or for leading-in conductors into houses or for other high-tension apparatus -may also be made as a multiple duct. Such a multipleduct also has the form of a. plate of insulation. One form of such a plate n. shown in Fig. 5 in section. The ducts are 4 provided at a', a. 'The condenser cover is made in the form of a plate, in which metallic1layersr and s are embedded. Thel dis:

tane between the layers is so Vselected that the voltage can be dealt with Without danger ci rupture. 4

' When a transformer has been mounted in an oil container the latter will be covered by In the case of conductors being led 'into a house the plate will be mounted at one end of the 1 duct likea Window pane. Instead of `two ducts, more thereof may be provided if desired. The ducts may also be used in cony 'junction with cylindrical insulators.

layers r 'and s. 'plate is mounted a sheet of glass t which layers maarre The plate is preferably provided with a lWeatlier-proof coating which may beinade in various Ways.

Fig. 6 shovvs' one example of such a coating, it being; assumed that Athe plate has two ducts a', c', as described above. The plate consisting of insulation is made as a con denser comprisin r the metallic insertions or n one or both\sides o2 the must vbe intimately connected withthe plate in order that the air may be completely exeluded. 1 The ends and sides of the plate may I also'be provided with pieces ot" Alass or with an otherwise weatherproof coating; As Weatherproof material mica, for example, may be used. ln many cases, however, a weatherproof coating of varnish will suffice. Having now particularly described and ascertained the nature .of my said invention and in'what manner the same is to be per formed, I declare thatA What claim is: 1. A transformer comprising a casing, a cover of insulating material carried by said casing', spaced metallic discs embedded with in said cover,` and means for electrically connecting' one of said discs to said casing. 2. `A cover for transformers and tbe like comprising a body ot' insulating material, spaced metallic discs concentric'ally disposed wit-hin' said body, and a leading-out tube supported centrally of said body.

3. A cover for transformers-and the like comprising,r a body of insulating material, spaced metallic discs coneentrically disposed within said'body, a leading-out tube supported centrally of said body, and a condenser element Within said tube and electrically'connectedwith one o-s'aid metallic z discs.

QA cover for transformers and the like comprising a body of insulating material, spaced metallic discs concentrically disposed within said body, a leading-out tube supported,v centrally 1of said body, and a metallic cylinder embedded Within Said tube andl electrically connected with one of said metallic discs.

ln testimony whereof l allix my signature in the presence of two Witnesses.

' KURT FISCHER.

.l/Vitnesses:

J. WYNEN, d. D. Zrssnonn. 

